This invention is directed to a system for cleaning an apparatus. More particularly, the invention is directed to a system for cleaning an apparatus whereby the system comprises a nozzle assembly with the capacity to spray a thickened liquid composition. The thickened liquid composition may comprise a soil treating agent and surfactant and can be used to clean a variety of apparatuses, including paper making machines.
The deposition of contaminants in and on equipment such as boilers, cooling towers, food and beverage equipment, and pulp and paper processing equipment, can be detrimental to the efficiency of the various processes being conducted in the equipment. Moreover, the desired products generated from contaminated equipment typically display properties and characteristics that are inferior to products made in a contaminant-free environment.
In the pulp and paper industries, for example, internal and external components of equipment, such as equipment used during the dry-and wet-ends of the paper making process, are subjected to various inorganics as part of the processing steps to convert pulp into paper. During such a process, diluted pulp (i.e., pulp which is about 99% water) is distributed onto fast-moving screens where it begins to take the form of paper. Subsequent to distribution on the screens, water is removed from the pulp via gravity and vacuum pumps strategically placed about the apparatus. The resulting damp paper sheets are then pressed between felt blankets to remove additional moisture. The dried paper then moves from the felt blankets to heated cylinders of the paper making pulping apparatus so that the final paper product does not exceed about 6.0% water. Finally, the resulting final paper product may be subjected to a smoothing step before being rolled and shipped to customers.
As can be understood, the paper making process, like many other processes, is complicated. This is true because precursor paper raw materials are typically subjected to harsh environments that comprise many chemical and physical processing steps. Such chemical processing steps are known to generate a fair amount of waste and contaminants, and the apparatuses involved with these steps require cleaning to ensure that superior and contaminant-free product is being generated.
Conventional methods for cleaning internal and external portions of equipment, such as those described above, typically employ high volumes of solution and active that dissolve the contaminants associated with the equipment. The solution method, however, has many disadvantages, including the generation of excess environmentally unfriendly waste that typically has to be removed to off-site hazardous waste plants. Other conventional methods for removing contaminants from the internal and external portions of equipment include the use of high pressure water blasting (e.g., blasting at pressures that exceed at least 400 psi). Such a water blasting method, unfortunately, requires the expensive and labor-intensive steps of disconnecting the parts of the equipment prior to cleaning. Moreover, water blasting techniques are not very safe because the chemical solutions employed often splash onto the individuals conducting the high pressure water blasting.
In addition to the vast deficiencies of the conventional methods outlined above, such conventional methods require that the cleaning solutions be mixed and/or processed at a job site prior to use. Also, such conventional methods typically use cleaning solutions having about 50% by weight more active than the thickened liquid composition of the present invention.
It is of increasing interest to develop a system for cleaning apparatuses. More particularly, it is of increasing interests to develop a system that does not generate excess hazardous waste, can be conducted at low pressures and is safe to use. This invention, therefore, is directed to a system for cleaning an apparatus that does not generate excess hazardous waste, is conducted at pressures under about 100 psi is safe, and does not require processing of a chemical solution before use at job sites.
Efforts have been disclosed for cleaning in U.S. Pat. Nos. 5,977,050 and 5,705,470 cleaning gels that are dispensed from a hand held trigger or aerosol spray applicator.
Other efforts have been disclosed for inhibiting contaminant deposition in papermaking systems. In U.S. Pat. No. 5,885,419, the deposition of organic contaminants in a paper making system is minimized by adding albumins, globulins and spray-dried animal cells to the pulp, or by spraying deposition prone surfaces of the paper making system with the same.
Still additional efforts have been disclosed that convert inorganic materials in Kraft pulping liquor into pulping chemicals. In U.S. Pat. No. 5,034,094, pulp recovery is increased by separating organics and inorganics wherein the former is recycled to a process loop and the latter is converted into pulping chemicals without the need of a recovery furnace.
In a first aspect, the present invention is directed to a system for cleaning apparatus, the system comprising:
(i) a thickened liquid composition comprising a viscosity from about 50.0 cps to about 1,000 cps;
(ii) a spraying device comprising at least one orifice having a diameter from about 2.0xc3x9710xe2x88x922 cm at about 6.5xc3x9710xe2x88x921 cm; and
(iii) a pressure source supplying less than about 100 psi of pressure
wherein the thickened liquid composition comprises components that clean soil on the apparatus.
In a second aspect the present invention is directed to a kit comprising:
(a) a thickened liquid composition comprising a viscosity from about 50.0 cps to about 1,000 cps, the liquid composition comprising components that clean soil on the apparatus;
(b) a spraying device comprising at least one orifice having a diameter from about 2.0xc3x9710xe2x88x922 cm at about 6.5xc3x9710xe2x88x921 cm; and
(c) a pressure source supplying less than about 100 psi of pressure; and
(d) instructions to use the liquid composition supplied is and at a pressure that does not exceed about 100 psi.
In a third aspect, this invention is directed to a method for cleaning an apparatus with the system described in the first aspect of this invention.
Thickened liquid composition, as used herein, is defined to mean a liquid having a viscosity of greater than about 50 cps and less than about 1000 cps (at ambient temperature and taken with a Brookfield Viscometer, spindle No. 2), and soil treating agent is defined to mean a substance that can react with, neutralize and/or dissolve soil. Pressure less than about 100 psi generally means pressures from about 5 psi to about 99.99 psi, and preferably, form about 40 psi to about 80 psi, including all ranges subsumed therein.